Synthesis and characterization of X8R BaTiO3-based dielectric ceramics by doping with NiNb2O6 nanopowders

Abstract

High performance X8R BaTiO3-based ceramics with pure perovskite phase were prepared by nanocomposite doping method. The phase structure, dielectric and electrical properties and the “relaxorlike” characteristic of ceramic materials are systemically studied. According to XRD and TEM analysis, the nanocomposite dopants via sol–gel method are uniform and well dispersive. The role of NiNb2O6 on dielectric properties and phase structure of BaTiO3-based ceramics is investigated. The properties comparison of samples prepared by nano-doping and conventional process is accomplished. SEM micrographs reveal that the grain size of BaTiO3-based samples is more uniform by nano-doping process. Meanwhile, bulk densities and dielectric properties are enhanced. The 1.5 wt% NiNb2O6-doped sample sintered at 1280 °C shows the optimal dielectric performance (ɛr = 4160, tanδ < 1.0 %, ΔC/C20 °C ≤ ±15 %) that satisfied EIA–X8R specification.